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The dominant role of the magnetoresistance effect caused by spin electron scattering in the oxygen evolution reaction is unveiled through an in situ tunable magnetic field-electrochemical testing system.

universal anode reaction for water electrolysis, carbon dioxide reduction, and metalair batteries, which usually requires the use of noble metal catalyst due to the sluggish kinetics. [1] However, due to the high cost and scarcity, large-scale application of noble metals is greatly restricted. Therefore, the development of non-noble metal catalysts with high efficiency and low cost is of great importance. In particular, transition metal-based layer double hydroxides (LDHs) have attracted extensive attention because of their facile synthesis and adjustable composition. [2] The OER performance of LDHs is limited by active sites and poor intrinsic activity. [3] Moreover, due to their semiconductor characteristics, a Schottky barrier may be formed when contacting the conductive substrate, which greatly hinders the charge transfer. [4] A variety of strategies, including size modulation, composite with conductive materials, heteroatomic doping, defect engineering, and interface engineering, have been investigated to further regulate the OER performance of LDHs. [5] It is noteworthy that adjusting the electronic structure of the catalysts can optimize the adsorption energy of the intermediates and improve the reaction kinetics. [5c] In this regard, the construction of p-n heterojunction is a promising strategy to regulate the local electronic structure of catalytically active sites, as the difference of Fermi level (E f ) between n-type semiconductor and p-type semiconductor results in the spontaneous flow of electrons at the interface to achieve thermal equilibrium. As a consequence, the activity, selectivity, and stability can be substantially improved by binary catalysts when compared with single-component catalysts. For example, the p-n junction in FeNi-LDH/CoP with positively charged FeNi-LDH in the space-charge region could greatly improve the OER performance, [6] and the formed CuO@CoOOH p-n heterojunction could remarkably modify the electronic properties and serve as an excellent OER catalyst. [7] In addition to ameliorating the catalyst materials, the emergence of intensification strategies by external fields such as gravity field, light field, ultrasonic, and electric field, has become a new trend in the field of electrochemistry, which can effectively improve the mass transfer on the electrode surface and change the reaction kinetics. [8] Interestingly, the latest research confirms that coupling the magnetic field with electrochemistry Here, a strategy to regulate the electron density distribution by integrating NiFe layered double hydroxides (NiFe-LDH) nanosheets with Co 3 O 4 nanowires to construct the NiFe-LDH/Co 3 O 4 p-n heterojunction supported on nickel foam (NiFe-LDH/Co 3 O 4 /NF) for electrocatalytic oxygen evolution reaction (OER) is proposed. The p-n heterojunction can induce the charge redistribution in the heterogeneous interface to reach Fermi level alignment, thus modifying the adsorption free energy of *OOH and improving the intrinsic activity of the catalyst. As a result, NiFe-LDH/Co 3 ...

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Poly(dodecafluoroheptyl methacrylate) (PDFMA)/titanium dioxide (TiO2) nanocomposites with high TiO2 content were successfully prepared by emulsion polymerization process. Before polymerization, nano‐TiO2 was pretreated by silane coupling agent. Surface groups and composition of the modified nano‐TiO2 were characterized by Fourier transform infrared and X‐ray photoelectron spectra. The microstructure of nanocomposites was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In addition, the thermo‐stability and wetting behavior were also investigated in relation to the dosage of TiO2. The results showed that the thermostability is improved with the increment of TiO2 content while hydrophilic properties exhibit nonlinear variation with the content of TiO2. The optimal percentage of TiO2 content in the TiO2/PDFMA nanocomposites is 30% that could lead to the higher thermostability and hydrophobicity properties of composites. The maximum water contact angle (WCA) of nanocomposites can reach 120° ± 1°. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44377.

The photocatalytic activity of anatase-structured Ti(1-(5x/4))Nb(x)O(2-y-δ)N(y) (x = 0.25, y = 0.02; NbN-25) was examined for water oxidation under UV and visible light irradiation. The semiconductor was prepared by sol-gel processing followed by nitridation in flowing ammonia and exhibits an indirect optical gap of 2.2 eV. Ti(1-(5x/4))Nb(x)O(2-y-δ)N(y) was loaded with RuO2 by an impregnation technique, and optimized conditions reveal that 1 wt % RuO2 generates 16 μmol O2 from water with concomitant IO3(-) reduction after 3 h of illumination under simulated solar radiation at a flux of 600 mW/cm(2) illumination, which corresponds to 6-sun AM1.5G illumination (compared to no detectible O2 without the RuO2 cocatalyst). A series of cut-on filters shows that the catalyst-loaded semiconductor evolves O2 for λ ≤ 515 nm, and a gas-phase mass spectrometry isotope labeling experiment shows that irradiating an iodate solution in H2(18)O in the presence of 1 wt % RuO2 loaded on NbN-25 gives rise to catalytic water oxidation: both (36)O2 and (34)O2 are observed. It is unclear whether (16)O arises from IO3(-) or surface reconstruction on the photocatalyst, but ICP-AES analysis of the postirradiated solution shows no dissolved metal ions.

A subgroup H of a finite group G is said to have the semi cover-avoiding property in G if there is a normal series of G such that H covers or avoids every normal factor of the series. In this paper, some new results are obtained based on the assumption that some subgroups have the semi cover-avoiding property in the group.